Another 97 EJ22 here... they just keep going! Mine hasn’t lived an easy life but it's a great beater.

9.050Wh, not kWh. 1,810mAh/1000 gives you Ah, and 1.81Ah * 5V = 9.050Wh. If it took 9kWh to charge your phone every night you would be paying 30+ dollars a month just to charge your phone!